A Bay Area yoga instructor has been fired from her job after a student she was teaching at the Facebook headquarters complained about the instructor's reaction to her in-class cell phone use.

Alice Van Ness, 35, has been teaching yoga since 2006. As a courtesy, as class begins she says she politely asks students to turn off their phones. But while teaching at the Facebook Fitness Center last month, the northern California native said one student -- who she says had been texting at the beginning of class – began using her phone while she was demonstrating the difficult half moon pose.

"When she picked up her phone, I was surprised," Van Ness told ABC News. "I didn't know what to say. I just looked at her with this look of utter disbelief. Like, 'Really? You're going to do that right now?'"

That look of disapproval cost Van Ness her job with Plus One Health Management, the company that operates the gym out of Facebook's Menlo Park, Calif. offices. Two weeks after the incident, Van Ness was dismissed by the company.

Van Ness says that the Facebook employee -- who she would only identify as "not [Facebook COO] Sheryl Sandberg" -- was in the middle of the front row of the class of about 10. When the class stopped as she typed on her phone, she quickly left the room. The woman then went to complain -- possibly directly to the Van Ness' manager -- that she felt humiliated by the incident.

Van Ness says that she didn't say anything to the woman, who shortly after making her complaint known, rejoined the class.

"I did not know what to say. I didn't want to make a huge deal out of it. It's the first time that someone did it, at such a time right in the middle of class," she says.

According to Van Ness, who has over 500 hours of training in the San Francisco Bay Area and in Seattle, there was no discussion with her supervisors as to what happened the day in question. She says that when she came in two weeks later, they had her final paycheck and termination papers ready.

Calls placed by ABC News to Plus One Health Management regarding the incident were not immediately returned. Slater Tow, a Facebook spokesman, told the Mercury News that since Van Ness is not its employee the company has no comment.

Van Ness told the Mercury News that her termination letter noted that the employee said Van Ness had "made a spectacle of her" during class by stopping instruction and glaring at her.

Van Ness, who also taught pilates and cycling classes at Facebook, is questioning how much we all need to be plugged in, and what we would be missing online if we were to disconnect out of respect to those around us.

"It's about respect for instructor, and those in class," she says. "It's etiquette to give attention to the teacher -- or even if you're having lunch with friends. I just think it's kind of rude, even to answer your phone during a meal.

"If you're into yoga, you should pay attention to your body. The few times I've gotten hurt, I'm not paying attention," she adds.

Since she was fired, Van Ness has quickly bounced back, landing a new part-time administrative position through friend, along with some writing gigs.

She is also still going to teach yoga and fitness, but thinks that her days teaching in corporate settings -- where she says students often arrive late, leave early and interrupt class -- are likely over.

"If they didn't want to fire me, I would have quit. It's the last straw. It's not the type of teaching environment for me," she said. "I have students who want an environment where they don't want to use their phone. Those are the students I want. If they' don't want to learn something, and just breeze in and out of yoga, maybe that's not the environment for me."